Mughelli, 32, was released by the Atlanta Falcons on May 8. He played seven games with the Falcons last year before a knee injury cut his season short.

The 2003 fourth-round draft choice of the Baltimore Ravens went to the Falcons after four years and signed a six-year, $18 million deal with Atlanta. That 2007 deal was considered to be the biggest ever given to a fullback.

Mughelli was a Pro Bowler in 2010.

The Falcons needed to clear salary cap space after trading for cornerback Asante Samuel, so Mughelli was released. He had been due to earn $3 million this season. Atlanta also drafted fullback Bradie Ewing of Wisconsin in the fifth round.

Mughelli, known as a strong run blocker, will compete with Brit Miller and undrafted rookie Todd Anderson for the starting fullback job for the Rams.